Study On Total Synthesis Of Chiral Flavanones And Flavonoids Benzopyran Natural Products

This thesis focuses on the study of the total synthesis of several chiral flavanones, Benzopyran flavonoids and amide natural products. The thesis includes five parts as follows:The first part introduces several different methods of synthesis of chiral flavanones and synthesis of chiral flavanones derivatives.The second part presents ammonia-based chiral catalytic asymmetric synthesis of chiral flavanones.Chalcone synthesis was produced by conventional methods. Then in the experiment we screened various chiral amine catalyst, which was used to work with chalcone role under a series of optimized reaction condition, the ultimate synthesis of two kinds of chiral flavanones. Enantioselectivity was measured by HPLC method.The third part mainly introduces the total synthesis of (±)-Cycloaltilisin7 and (±)-Dicromenochalcone.Starting from 2,4,6-hydroxyacetophenone and p-hydroxybenzaldehyde, with benzopyran, hydroxylation protection, aldol condensation, deprotection, cyclization and other steps, the first synthesis of the natural product (±)-Cycloaltilisin 7; when benzopyran, generating an important intermediate of synthesis natural products (±)-Dicromenochalcone, and therefore natural product by anti-leishmaniasis activity, it will be important intermediates with p-methoxybenzyl benzaldehyde role in 53% yield synthesis of (±)-Dicromenochalcone.The fourth part introduces the synthesis of a new chapter geranyl chalcone (±)-Poinsettifolin B.Poinsettifolin B is a new geranyl chalcone extracted from Sankoh Okinawa Morus Dorstenia Poinsettifolia, which is useful for the treatment of infected wounds and civil yaws, with 2, 4-hydroxyacetophenone,3,4-hydroxybenzaldehyde as a starting material for the first time to complete the synthesis of Poinsettifolin B, in 60% yield.The fifth part mainly introduces the synthesis of bis-amide.A natural product, N, N’-diferuloyl-putrescine (DFP), was prepared by condensation reaction of ferulic acid with 1,4-diaminobutane. First synthesis of JBIR-94 with total yield of 77.1% was accomplished by reduction of DFP using Pd/C as the catalyst.All structure of new compounds were confirmed by 1H NMR,13C NMR and IR.